Experimental Studies of Plasmonic Nanoparticle Effects on Organic Solar Cells

Abstract

The incorporation of plasmonic nanoparticles (NPs) into different layers of organic solar cells (OSCs) is studied in this chapter. First, we incorporate NPs into the hole collection layer of OSCs. The resulting improvements in Power Conversion Efficiency (PCE) are found to originate mainly from improvement in hole collection efficiency, while Localized Surface Plasmon Resonance (LSPR) effects are found to have negligible effect on active layer absorption. Next, we incorporate NPs into the active layer of OSCs. In this case, the absorption of the active layer improves, but we also showed that consideration of electrical properties including carrier mobility, exciton dissociation efficiency, and active layer morphology is required to account for the PCE trend. In both studies, we theoretically show that the very strong near field of NPs is found to distribute laterally along the layer in which the NPs are incorporated in, and hence leading to active layer absorption improvements only when NPs are incorporated into the active layer. Lastly, we incorporated NPs into both active layer and hole collection layer in which the accumulated effects of NPs in the different layers achieved ~22 % improvement in PCE as compared to the optimized control OSCs using poly(3-hexylthiophene): phenyl-C61-butyric acid methyl ester (P3HT:PCBM) as the active layer.